<user_name @ sys_name : cwd>
~ is the place where the executable shell is present.

ls <directory name> -a -l
the flags and the directory name can be given in any order.
Even ~ related paths can be given.

cd <directory name>
if the directory exits then it changes the directory to the one provided.

echo <anything>
prints out the string given removing the extra spaces in between.

pwd
prints the pwd of the shell.

pinfo <pid>
if no pid is provided , the pinfo of the shell is printed.
for a given pid , the required info is printed.

bg - if the processess are given without & at the end , the process is run and shell waits till it's completion.
fg - it prints the pid of the process that is just made.
     after the process ends, it gives info about the process that ended and the exit status.

many commands can be given seperated by a ';' and there are run sequentially.

history <Number>
gives the latest (<=)10 commands entered in the shell.
given Number(<=10) , it prints that many number of latest commands from history.